Field of the Invention
The invention relates to a control device in a motor vehicle.
A control device for a motor vehicle for detecting an impact or a linear deceleration resulting from an impact is preferably used in a control device for at least one vehicle-occupant protection device of the motor vehicle. Conventional control devices detect and process decelerations which are parallel and transversal with respect to the longitudinal axis of the vehicle. Conventional vehicle-occupant protection systems for motor vehicles correspondingly have a control device, at least one restraining device for side impact protection in each half of the vehicle and at least one restraining device for head-on impact protection. The former restraining devices are preferably side air bags and/or head air bags and the latter are preferably driver and/or front seat passenger air bags and/or seat belt retractors.
A configuration which is disclosed in U.S. Pat. No. 5,544,915, for detecting an impact from the side and an impact from the front, has a sensor configuration which contains a transversal acceleration pick-up in the form of a transversal acceleration sensor in each half of the vehicle. In order to detect an impact from another direction, the proposed sensor configuration has a control unit disposed centrally in the vehicle which contains a longitudinal acceleration pick-up with two acceleration sensors that are aligned at .+-.45.degree. with respect to the longitudinal axis of the vehicle. The central control unit also has an evaluation device which firstly detects impacts and/or decelerations in terms of strength and direction in a plane which is determined by the longitudinal axis of the vehicle and the transversal axis of the vehicle, as a function of the signals of the motor vehicle. Therefore, in particular in the case of impacts from the front, from the side or at a different angle in the plane, the restraining device for head-on impact protection is triggered with the aid of the two longitudinal acceleration pick-ups, and the restraining device for side impact protection is triggered as a function of the signals of the transversal acceleration pick-ups.
In addition, configurations for detecting a rotational movement of a motor vehicle are known which make use of a rotational movement sensor, which is also referred to as rotational speed sensor, that is used in particular for the purpose of detecting tilting of the vehicle about its longitudinal axis. Such rotational movement sensors are disposed approximately at the center of gravity of the vehicle and are aligned in accordance with a roll-over movement to be picked up. Rotational movement sensors can operate according to different physical principles.
German Published, Non-Prosecuted Patent Application DE 41 10 374 A1 discloses a device for sensing a roll-over movement through the use of two linear acceleration sensors. A rotational movement variable is determined from the acceleration signals and the driving stability of the motor vehicle is controlled as a function of the rotational movement variable.